Luna had released Twilight from the Cryogenic Time Chamber. It was Luna's grande plan. Twilight took over Luna's body, where Luna entered the Ethereal realm.

It's because of Luna, Equestria has been blown up…

~This is a ponified version of my Black ops 2 actual storyline. if you didn't know…
Celestia = Maxis
Luna = Richtofin
Twilight = Samantha.
Thank you.~